(1) Field of the Invention
This invention relates to tools, and more particularly to a decoupling tool for unlocking a fifth wheel assembly to allow decoupling of a trailer from a tractor.
(2) Description of the Related Art
In large highway transport vehicles of the tractor-trailer type, an assembly commonly referred to as a fifth wheel is mounted on the rear of the tractor above the drive tires for coupling of a trailer to the tractor. The fifth wheel assembly has a locking device that receives an independent kingpin attached to the trailer and allows the trailer to pivot when attached to the tractor.
The fifth wheel assemblies, although varying somewhat from one manufacturer to another, are all basically the same with regard to their configuration and operation. In general, fifth wheel assemblies will automatically lock the trailer's kingpin in place when backing the tractor into a trailer therefore causing the fifth wheel to engage the locking jaws around the kingpin. Fifth wheel assemblies are provided with a release, or unlocking handle which, in most cases, must be manually pulled so that decoupling of the trailer from the tractor can be accomplished.
As is well known in the art, pulling the release handle to unlock the fifth wheel assembly can be a very dirty job and often times difficult thing to accomplish. In some cases the operator has sustained injuries related to this difficult duty.
The pivot operation of fifth wheel assemblies requires that they be covered with grease for proper operation, and they are almost constantly being subjected to mud, slush, snow, road tar, and other contaminates due to their physical location adjacent to the rear wheels of the tractor. The grease and road contamination, both on the fifth wheel itself and the surrounding areas such as the tractor's wheels and the frame and the underside of the trailer, make this less than ideal place to which the vehicle's operator must reach or crawl in order to pull the fifth wheel release handle.
When both the trailer and the tractor are on a substantially level, or evenly sloping surface, manual pulling of the fifth wheel release handle is usually an easy thing to accomplish. However, if the angular rotation of the trailer about its longitudinal axis differs from the angular rotation of the tractor about its longitudinal axis, the locking mechanism of the fifth wheel assembly can be subjected to binding forces which make it difficult, if not impossible, for anyone to pull the release handle. Such binding is not an infrequent occurrence, and when it does occur, the vehicle's operator has heretofore been required to reposition the tractor and the trailer until he achieves a substantially aligned position. Sometimes the properly aligned position of the tractor and trailer can be achieved with a single repositioning maneuver, and sometimes the operator will spend considerable time before he achieves the required alignment.
This repositioning of the tractor and trailer to relieve binding of the fifth wheel can be a very time-consuming and costly operation, which, in conjunction with the inherently dirty area, can be very frustrating to the operator of the vehicle, and costly to him/her with regard to ruining clothes, bodily injury, and time.
The other main issue this tool addresses is the tandem release for the tandem tires on the trailer of the tractor trailer assembly. The tandem pins may be released in order to balance the weight of the trailer better. In order to do this, the tandem lever, located under the trailer near the tandem tires, must be inserted into the locking slot. This can be a very difficult and sometimes next to impossible job for one person if the pins are wedged slightly out of place. There are several tools to assist in releasing the tandem pins; however, these tools can break easily or not provide enough leverage to release the pins. At times it takes several persons to release the pins. The said invention provides not only strength, but also leverage to maneuver the pins.
The tool also provides a tire pressure check device and spotter tool on-board to assist a driver in checking the actor-trailer for safety and maneuvering the tractor-trailer into tight locations. This exists in separate tools; however, with the limited space provided in a tractor, the on-board tool creates a simplified and convenient location for storing several tools in one.
To the best of my knowledge, no new or improved device has been developed or suggested for assisting the operator in such tractor-trailer decoupling operations or load-balancing operations. Therefore, a need exists for a new and useful decoupling/load balancing tool, which facilitates the unlocking of the fifth wheel assemblies.